IV Difference Guide — 15/15/15 vs 15/15/14
15/15/15 vs 15/15/14 — how much does it actually matter?
TL;DR
In most cases, a single IV point is imperceptible. Pokémon GO damage calculation uses floor() (rounding down), so even with 1 lower IV the actual damage is often identical.
Why no difference?
Pokémon GO damage formula:
The key is floor (round down). Whether the result is 45.8 or 45.2, the actual damage is the same 46 (with +1).
Effective Atk difference between IV 15 and 14 is 0.7903 (Lv40 CPM). This tiny gap gets floored away, resulting in identical damage.
Real Examples
Damage per ATK IV for raid matchups you'll actually use. Lv40.
| ATK IV | Effective ATK | Damage |
|---|---|---|
| 15 | 218.1 | 158 |
| 14 | 217.3 | 158= same as 15 |
| 13 | 216.5 | 157 |
| 12 | 215.8 | 156 |
| 11 | 215.0 | 156 |
| 10 | 214.2 | 155 |
| ATK IV | Effective ATK | Damage |
|---|---|---|
| 15 | 198.4 | 102 |
| 14 | 197.6 | 102= same as 15 |
| 13 | 196.8 | 102= same as 15 |
| 12 | 196.0 | 101 |
| 11 | 195.2 | 101 |
| 10 | 194.4 | 100 |
| ATK IV | Effective ATK | Damage |
|---|---|---|
| 15 | 215.0 | 131 |
| 14 | 214.2 | 131= same as 15 |
| 13 | 213.4 | 130 |
| 12 | 212.6 | 130 |
| 11 | 211.8 | 129 |
| 10 | 211.0 | 129 |
* The threshold where damage changes is called a "breakpoint." A 1–2 IV difference rarely crosses one.
What is a Breakpoint?
A Breakpoint is the attack threshold where damage increases by one.
In this case only ATK 15 gives +1 damage. These cases are rare.
Most move/defender combos have ATK 13–15 dealing identical damage. Breakpoints falling exactly between 14 and 15 occur in less than ~10% of cases.
What about DEF/HP IV?
DEF and HP IVs work the same way. The 14 vs 15 difference is negligible.
Damage taken has "bulkpoints" that work the same way. Surviving one extra hit thanks to DEF 14 vs 15 is extremely rare.
1 HP IV difference = 0.8 actual HP difference. Less than 0.5% of total HP at Lv40 — imperceptible.
IV Differences in Master League
Master League has no CP cap, so 15/15/15 is optimal. Many people still worry "is 14/15/15 okay?"
When both sides fire a Charged Attack on the same turn, the higher effective ATK goes first. In mirror matches, ATK IV 15 vs 14 can decide CMP.
Mirror matches don't happen every battle, and even in mirrors, both sides firing Charged Attacks on the exact same turn is uncommon.
You also can't know if the opponent has ATK 15, so CMP actually deciding the outcome happens in only a tiny fraction of battles.
Casual Master League play. Damage diff is minimal and CMP rarely matters.
Top-tier Master League (Legend push). For meta Pokémon with frequent mirrors (Dialga, Zacian, etc.), ATK 15 is recommended.